1. Field of the Invention
The present invention relates to a composition suitable for use in hoses, including automotive radiator coolant hoses, air conditioning hoses and steam hoses; and hoses comprising the composition.
2. Description of Information Disclosures
Hoses made from synthethic or natural rubbers and methods for producing the hoses are known. Hoses used to conduct fluids to and from automotive radiators are described, for example, in U.S. Pat. No. 4,096,888; U.S. Pat. No. 4,698,890; and U.S. Pat. No. 4,158,033, the teachings of which are hereby incorporated by reference.
Although there are many commercially available types of automotive radiator hoses, there is still a need to improve the properties of these hoses, such as resistance to water or coolant diffusion, heat resistance and compression set.
Rubber based steam hoses are also well known in the art. One problem with such hoses is that moisture often permeates the rubber portion of the hose. When the moisture is cooled and then reheated, the trapped moisture can cause the formation of blisters or partial blowouts. This effect is known as "popcorning".
Because of its good impermeabilities, halogenated butyl rubber has been used for steam hoses in an effort to reduce this popcorning effect. There exists, however, a continuing need for hose compositions with improved impermeability and heat reistance.
It has now been found that hoses that are made from a composition comprising certain halogen-containing copolymers of a C.sub.4 to C.sub.7 isomonoolefin and a para-alkylstyrene containing a critical amount of the para-alkylstyrene moiety and a critical amount of chemically bound halogen have improved properties.